I just got an old Curtis air compressor from a friend. Not sure on year yet I'm in the process of restoring right now trying to free the piston. I have a question there is a chamber on the side of the cylinder that was capped had a wad of what looked like steel wool in it Not sure what this is. My first thought was air intake but one there is an intake with filter on the head and two it seams to have an opening into the cylinder at the very bottom where the piston never passes. So confused what this could be
Old Curtis air compressor
- Thread starter Scott3236
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slowzuki
Well-known member
I've got an old compressor with a fine mesh screen in a similar location that was plugged up with overspray. I just cleaned it an put it back in place. Its a crankcase vent of some type. Clogged it was pushing a lot of oil out the drive sheave side of the compressor.
Fretters
Well-known member
Crankcase vent sounds right. The wire wool is just a filtering material, Scott. Simple yet effective. Similar to the old oil bath intake filters. They merely used a mesh in conjunction with oil.
With regards the seized bit, (what's seized exactly?), thin oil, diesel, paraffin, (kerosene) etc. are all plausible options for popping in there to let it soak. Give it a day or two, for whatever you use to work its way in there, before trying to free it.
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The piston itself is siezed in the cylinder The top of the cylinder all the way down to where the piston is sitting looks clean not rusted so must be at the very bottom where it is sitting I usually use a 50/50 mix of atf and acetone
I was wondering if it was a breather like thing. Makes sense
I was wondering if it was a breather like thing. Makes sense
Fretters
Well-known member
Best thing to do then is just pop your freeing solution of choice into the top of the cylinder and then let it sit for a couple of days. I normally get a piece of softwood, of a diameter just large enough to fit into the cylinder, and tap the top of the piston with that, after it's sat for a few days. You can always tap the piece of softwood with a hammer if you want a bit more force, but just don't go to excess. You'll likely find that the rings just have a slight rust layer on them which is binding them to the cyinder wall.
I haven't let it soak yet but that's the plan. It's de stuck very good When I first got it I popped off the oil fill plug to check oil. Looked watery and very low figured I'd give it a spin by hand. Wouldn't e budge that's when I started disassembly. Going to clean everything up inspect the tank and try to get her goin again
Fretters
Well-known member
If that isn't a retaining ring/clip for anything inside, then that may well be what they use for splash lubrication. They had a similar system on some of the the old lineshaft pillar drills, where a ring of leather, steel or similar would just sit on the shaft, dangling in the oil bath, and lube the shaft as it rotated.
Thank you that I think proves my theory that that's what it's for. No way it holds anything in it just dangling there and is on the crank on one end and under the oil level rod on the bottom. So I *** it was for oiling but have never seen anything like it before
slowzuki
Well-known member
Kellogs used an oiling ring too.